My Dell Inspirion 6000 Notebook has the dreaded Blue Screen with c000021a (Fatal System Error) and will not boot to Windows. This has happened numerous times and the problem has been resolved by reloading Windows XP and the drivers and software. The system will work temporarily, but eventually shuts down and returns to the blue screen. It seems Windows XP gets erased every time the system crashes. I'm assuming the problem is either my harddrive or the motherboard. How can I tell which one is causing the problem?